MINNEAPOLIS - As investigators in Washington State determine the cause of a bridge collapse that injured several people, Minnesota officials are reflecting on our own bridge collapse.

2007 wasn't that long ago.

The 35-W Bridge collapse raised questions about inefficient and inadequate bridge inspections, putting one of the state's largest government agencies under scrutiny.

In nearly six years, a lot has changed.

"One of the first things that took place after the bridge collapse was an investigation," says Nancy Daubenberger, State Bridge Engineer for MnDOT.

Government officials promised to inspect every bridge, which includes about 4,500 on the state highway system.

Daubenberger chief says that has happened.

The legislature created a bridge program, which is called Chapter 152. The program in part, funds inspections, repairs and replacement.

At the time 35-W fell, the state considered 72 bridges fracture critical, meaning if one load bearing component failed, the entire bridge could.

According to a 2013 report to the legislature, to date, nine fracture critical bridges have been replaced, including the DeSoto bridge in St. Cloud.

Another 11 will be replaced by 2018, like the Lafayette in St. Paul and the Hastings Bridge.

The rest aren't ready for replacement now, but at least 10 more will be in about 15 years.

As for inspections, MnDOT has about 50 more bridge inspectors today than it did in 2007.

However, while the state likely knows more about its bridges than ever before, money earmarked in the bridge program - $2.5 billion in state, federal and bond money - will run out in 2018, as bridges continue to deteriorate.

"We have a quite an era of bridges that were built during the interstate era, a generation of bridges that were built then that are going to be coming due toward the end of the Chapter 152 ...so a major investment in bridges will be needed at that time as well," says Daubenberger.

MnDOT officials estimate that the agency will need just under $5 billion for bridges from 2018 to 2033, a 15 year period. Where that money comes from when current funds dry up will no doubt be up for discussion in the coming years.

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